This invention relates automobiles, and more particularly, to a steering wheel in an automobile which has a vibration prevention mechanism, and a horn switch mechanism.
A steering wheel having a vibration prevention mechanism and a horn switch mechanism has been proposed by Japanese Utility Patent Application (OPI) No. 3827.5/1990 (the term "OPI" as used herein means an "unexamined application"). The vibration prevention mechanism prevents the ring section of the steering wheel from being vibrated by the oscillation of the engine which is transmitted through the steering shaft.
In the above-described steering wheel, the horn switch mechanism comprises: first and second plates having contacts which are brought into contact with each other to operate the horn; coil springs interposed between the first and second contact plates to space them away from each other; and guide pins inserted into the first and second contact plates, to guide the movement of the second contact plate towards the first contact plate.
In the vibration prevention mechanism, annular vibration proofing rubber members are engaged with the cylindrical walls of guide pin inserting holes formed in the second contact plate, and the coil springs of the horn switch mechanism are provided between the first contact plate and the vibration proofing rubber members.
The above-described conventional steering wheel has the following disadvantages. In order to operate the horn switch mechanism, it is necessary to push the second contact plate towards the first contact plate against the elastic forces of the coil springs. In this operation, the pushing motion is abruptly stopped when the contacts of the first plate are brought into contact with the contacts of the second contact plate; that is, since the horn is not smoothly operable, the operator may not experience a comfortable response when pushing the contact plate.